In a variety of radiography such as medical radiography for diagnosis, a radiographic intensifying screen is generally used in combination with a radiographic film. The radiographic intensifying screen generally comprises a support, a phosphor layer and a surface protective layer overlaid in order. Since the surface protective layer is provided to keep the phosphor layer from chemical and physical deterioration, the protective layer must have a thickness enough to protect the phosphor layer. However, if the surface protective layer is too thick, the sensitivity lowers and further the resultant image is liable to shows poor sharpness. In order to solve this problem, many studies have been done.
In a generally employable radiographic intensifying screen, a typical material for the surface protective layer is a polyethylene terephthalate film having a haze of 5 to 10.
German Patent Publication No. 3,111,831 discloses a surface protective layer containing .gamma.-alumina particles in an amount of less than 0.1 wt. %.
Japanese Patent Publication No. 60-34720 discloses a surface protective layer wherein an organic matting agent is introduced to improve slip property of its surface.
Japanese Patent Provisional Publication No. 62-137599 discloses a surface protective layer in which polymer fine particles are introduced so as to improve slip property of its surface.
Japanese Patent Provisional Publication No. H3-28798 discloses a radiographic intensifying screen which comprises a protective layer having a great number of very small convexes or concaves on its surface.
Japanese Patent Provisional Publication No. 51-127688 discloses a radiographic intensifying screen which comprises a protective layer having a great number of very small convexes of matting agent.
Japanese Patent Provisional Publication No. 53-66392 discloses that a light-scattering layer is provided between the phosphor layer and a silver halide emulsion layer so that production of black spots by radioactive isotope can be prevented.
Japanese Patent Provisional Publication No. 58-58500 discloses a radiographic intensifying screen which has a white light-scattering layer provided on the phosphor layer, and a transparent protective layer provided on the light-scattering layer.
Japanese Patent Provisional Publication No. H3-255400 discloses a radiographic intensifying screen in which metal oxides are provided between the phosphor layer and the surface protective layer so that the screen can have electroconductivity.
The known surface protective layers such as described above have been developed in consideration of protection against chemical and physical deterioration (e.g., scratch resistance, stain resistance and abrasion resistance), as well as sharpness of the resultant radiation image. However, although these known surface protective layers are improved to a certain extent, their properties are still unsatisfactory.